V. Premnath, D. Kannan, I. Khalek, J. Jeevarajan
UL Research Institutes,
United States
Keywords: Sodium ion battery, thermal runaway, emissions
Summary:
Sodium-ion batteries are gaining recognition as a viable and cost-effective alternative to lithium-ion batteries due to the abundant availability of sodium. Multiple chemistries of sodium-ion batteries are commercially available, with layered metal oxide-based batteries being more common. When sodium-ion batteries are subjected to certain off-nominal conditions, they may experience thermal runaway which is accompanied by the release of gaseous and particulate emissions, posing a severe risk to human health and the environment. There have been very limited studies that have characterized these emissions in detail. This study examines thermal runaway emissions from four different commercially available sodium-ion cells with different capacities/formats. Experiments include tests at two different states-of-charge (SOC, 50% and 100%), and tests were conducted in triplicate to understand the repeatability/variability of these events. Particulate emissions was characterized in terms of particulate matter mass (PM2.5), real-time particle number/size and real-time black carbon, while gaseous emissions were characterized in real-time using Fourier Transform Infrared Spectrometry. This research provides critical insight into hazards associated with failure of sodium-ion cells which will help first responders, as well as, in the development of mitigation and control strategies.